cap

1 a covering for the head usually having a shaped crown grabbed a cap and plopped it on his head before running out Synonyms cap, chapeau, headdress, headgear, headpiece, lid [slang]Related Words baseball cap, beret, billycock [British], biretta, boater, bonnet, bowler, calotte, capuche, casque, castor, cloche, cocked hat, cowboy hat, cowl, derby, fedora, fez, garrison cap, hard hat, helm, helmet, high hat, homburg, hood, kepi (also képi), kufi, leghorn, miter (or mitre), nightcap, opera hat, overseas cap, panama, picture hat, pillbox, plug hat, porkpie hat, service cap, shako, silk hat, skimmer, skullcap, sombrero, sou'wester, Stetson, stocking cap, stovepipe, sunbonnet, tam, tam-o'-shanter, ten-gallon hat, top hat, topper, toque, tricorne (or tricorn), turban, zucchetto; warbonnet

2 a piece placed over an open container to hold in, protect, or conceal its contents I can't find the cap to the milk bottle Synonyms cap, lid, topRelated Words dome, hood, roof; capsule, case, casing, covering, housing, jacket, sheath, shell

3 a real or imaginary point beyond which a person or thing cannot go a cap on player salary expenditures was suggested as a way to keep small market teams competitive Synonyms bound, boundary, cap, ceiling, confines, end, extent, limitation, line, terminationRelated Words extremity, fag end, terminus; border, brim, edge, margin, rim, verge; outside; bar, barrier, fence, hedge, restraint, stop, wall

to set bounds or an upper limit for the senator will propose a bill to cap prices for home heating oil Synonyms limit, circumscribe, confine, hold down, restrictRelated Words bar, block, hamper, hinder, impede, obstruct; constrict, contract, lessen, narrow, pinch, squeeze, tighten; quell, repress, suppress; number; modify, qualifyNear Antonyms broaden, expand, widen; overextend, overreachAntonyms exceed